DE2847183A1 - PROCEDURE AND CORRESPONDING DEVICE FOR PNEUMATIC ADVANCE BRAKING OF TRAILER VEHICLES IN GENERAL - Google Patents

Description

Fabbrica Italiana magnet! Marelli SoPoA », Via Guastalla 2, Milan

Method and corresponding device for pneumatic Advance braking of trailers - vehicles in general.

The present invention relates to a method and the corresponding device for pneumatic braking with advance of trailer vehicles in general

The purpose of the invention is the braking of trailer vehicles in advance or early braking of the trailer compared to the tractor and the possibility of simple adjustment of this braking, in particular the invention pursues the purpose of the formation of pneumatic devices, in particular servo distributors and automatic servo distributors doho trailer- Brake valves for switching according to the appropriate criteria for braking a trailer or carrying out the braking of this trailer, _etc.

There are already trailer brake valves known as automatic trailer brake valves in order to obtain the advance of this braking, with or without the possibility of regulating this advance Equipment acts on a spring, the bias of which is adjustable, and which is connected upstream of the adjustment chamber of this response piston

Therefore, in both of the cases under consideration, problems need not be taken into account in a simple and easy solution. the; For example, in the first case, the pre-tensioning of the leading spring must be easily adjustable by acting on the response piston while in the second case the compressed air behind the check valve is released during the venting process.

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ORIGINAL INSPECTED

The invention overcomes these and other deficiencies and allows Braking of the trailer with a specific and selected "advance" which is easy to adjust «,

D _a s inventive V'erfahren, according to which an aggregate of cylinder reaction columns in response to the air pressure from the air supply of the trailer and its moving part on shut-off devices for the air for the trailer brakes to change and switch the effect and / or the braking force applied to this trailer responds, is characterized in that a correspondingly regulated air pressure acts on one of the piston surfaces of the cylinder «reaction piston unit, while the pressure of the air source of the trailer is applied to the other piston surface, thereby activating the trailer's brakes according to a certain series order with respect to the brakes of the To operate the tractor.

The device for carrying out the method described above, which is provided with a cylinder-reaction piston assembly, the piston of which responds to the pressure of the air in the brake system, and in operative connection both with the moving parts of a second cylinder-piston assembly as well as with a switchable locking device, which connects the actuators of the trailer brakes either to the trailer's air tank or to the outlet, is characterized in that pneumatic throttling devices are provided to temporarily change the air pressure from the trailer's air tank, as well as means to change this over time applying air pressure to one end face of the reaction piston, which is opposite to that to which the air pressure of the trailer -Luftkessela is applied so that both sides of the question R _e are action piston acted upon by respective different pressures which allow the advance of the B _r emsung the Zugm achine «.

Preferably, the pneumatic throttle members consist of a pressure reducer, whose pneumatic chambers on the K _a of the cylinder mmern

mm 3 ~

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der-reaction piston unit and these chambers are connected to each other pneumatically _{9 by} means of the throttle member, through this pressure regulator, the moving equipment of which is influenced on the one hand by the action of spring means and on the other hand by the air pressures supplying the brake elements of the trailer

According to an advantageous embodiment of the device the pressure reducer is provided with regulating devices for changing the pressure, so that the different pressure and thus the exposure time the same on the piston of the cylinder-reaction-piston assembly to be changed.

The invention will now be described in more detail by means of the following description and with reference to the accompanying drawing, for example, with regard to a preferred embodiment of the device which is provided with a relay valve which makes the method according to the invention feasible, namely show:
FIG. 1 shows a schematic longitudinal partial section of the relay valve provided with the device according to the invention;

Figure 2 shows a graph showing comparison "- example shows the course of the characteristic curves between the Austeildruck in dependence upon the control pressure in a known relay distributor (dashed line) and in the relay distributor of FIG Λ (continuously drawn line).

As previously mentioned, the invention can be practically various Have training forms, in the sense that the device for carrying out the method is built into any equipment or can be combined with this, which is used to switch or control braking in a trailer.

For example, this device can be installed in a trailer brake valve or built into a relay valve as shown in the drawing.

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The trailer relay valve of Figure 1 has a housing 10, the Interior divided into a number of pneumatic chambers A, B, C, D by means of the partition walls 12 and 14 · and the pistons 16 and 18 is. The piston 16, as mentioned in more detail later, is in the chambers B and 0 freely adjustable and forms a reaction flask o The chambers A and B are each connected to an air tank provided on the trailer by means of connections 20, 22 pneumatic organs for actuating the trailer brakes directly (i.e. in the case of a trailer brake valve), or indirectly mitdes relay valve shown

The channels D and E are via the connections 24 and 26 each connected to the Aissenluft and the switching line, which leads to the distributor installed on the tractor

The piston 18 is acted upon by spring means 28, the effect of which opposes the effect of the compressed air, which is present in chamber E in each case. The piston 18 holds a tube 50, the interior of which by means of the radial bores 32 is connected to the Kamler D, and below with a Stöseel 34 ends “The end of the latter stands in poetic Operational connection with one of the elements 36 of a valve 36- »38 the is acted upon by spring means 4-0, the effect of which the other part 38 of this valve pair is pressed against the sealing seat holds, which is provided on the partition wall 12, in order to thereby "monitor the connection between the chambers A and B".

The plunger 34- is at the same time in the guide element for represents the reaction flask 16, which is provided on its central part with a crane 44, which is connected to the one between the tube

30 and the ram in question arranged support approach in operative and thereby to adjust the piston 18.

The chambers B and 0, which are above and below through the Rtaktionskolben 16 are pneumatic with chambers F and

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G connected, which are formed in an additional housing by a partition wall 4-8. The Zusatsgehause 46 is disposed laterally on the housing 10 and its! .Weist partition 43 at its middle part an opening on its _s hand a sealing seat for a throttling member ^ O, which is pressed against this seat by means of suitable spring means 52 _o

Above supports the housing 46 adjustably EIA sealing member or piston 54 'which 5S is provided with a shaft and together with the throttle member 50 cooperate kaan _o A spring 58 feeauf * schägt the piston 54 and is gehalert at its other end by means of a Stel Lech screw 60, which is provided with a Beötlfeigungskragen 62, in order to regulate the spring force ia ßege & pressure to the pressure built up, on the Arto described 3 © * ^ "& firmly of the chamber G The force given by the Eed @ i? 53 is greater than that on the part the spring 52 on the throttle organ. 50 force exerted · In short, the now better-operated organ represents a pressure reducer and the pressures controlled in turn act on the opposite sides of the reaction.

piston 16 for the function of the device and thus for carrying out the method according to the invention

The features of the method according to the invention will now also be described with reference to the graphic representation in FIG explained

With reference to the relay valve in the drawing and assuming this is in its rest position, the chamber E is connected to the outlet on the basis of the position assumed by the distributor of the brake system _{or the like}

The piston 18, together with the plunger J4, is through the Spring action 28 shifted upwards and © s results from it that the valve 38 closes the connection between the chambers A and B BC, while the latter chamber via the plunger 34 and

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is the terminal 24 connected to the outlet _o Therefore, the devices connected to the terminal 22 of the trailer B _r emsorgane un- are actuated.

In addition, the throttle member 50 is open in this state and thus establishes the connection between the chambers F and G, since, as already mentioned, the bias of the 58 on the part of the regulating member 60 is greater than the return force of the return spring 52j which acts on the throttle element in question.

It follows from this that in this state the chamber C via which the chambers G and S ^{1 is} connected to the outside, since, as already mentioned, the chamber B is connected to the outlet 24.

If the distributor of the brake system is actuated by the user, compressed air is fed into the chamber E and the piston 18 is moved downwards in counter-pressure to the spring 28 and actuates the Deppel valve 36-38. The plunger 34 first acts on the valve 36, blocking the connection between the chamber B and the outlet (connection 24). Then, and when the piston 18 is moved further, the plunger 34 opens the valve 38, so that the chamber A is connected to the duct B: the compressed air of the trailer container thus flows from the chamber A in question into the chamber B ₀

The compressed air in chamber B flows into the actuators the trailer brakes, which Jedech do not take effect, because the air pressure alone is not enough and this is because of the pressure drops and the small openings between the valves 38 and the assigned seats. 42 "

In addition, the air from chamber B flows into chamber F and via the throttle element into chamber G and from this latter into chamber Oo. It follows from this that on the end faces of the reaction piston 46 two equal and opposite pressures act and thus the piston 16 does not cause any reaction.

«-! ^T ) -

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Λ *

thrust against the spring-loaded piston 18, while the pressure P (see FIG. 2) rises rapidly and is independent of the switching pressure POo

Opening the valve 38 allows flow of Air from chamber A into chamber G and when the pressure in the latter has reached a certain set value, which is determined by the regulator 60-2, the piston 5 ^

acting pressure superior to the load given by the spring 58, so that the valve 50 is closed and thus the The connection between chambers B and G is interrupted.

The thrust of the reaction piston 16, which is directed upwards, is projected by the collar 44 on the resilient piston 18 in the opposite direction to the switching thrust due to the pressure present in the chamber E. This will keep the piston 18 under the control pressure Pound that of the discharge pressure P in equilibrium, while the pressure in question increases in proportion to the control pressure PO, as clearly G of by means of the curves with a solid line of the graph Darsbellun Figure 2 is shown _o

In this illustration, PO1 denotes the initial delivery pressure and P1 denotes the value of the V-pressure _o

This makes it possible, according to the relevant criteria, to bring the braking of the trailer forward in relation to that of the tractor, and to prevent this from happening too early. The advance is determined by the amount of pressure which is built up in each case in the chamber C of the cylinder reaction piston unit 10w16, _{or the like}

It is obvious that the device can be practically modified and changes and in particular what the MLtteL to the structure in the chambers B-O of the reaction unit 10- 16 concerns the temporally variable differential pressures and this in particular with regard to the required

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Features of the device _o This does not leave the scope of the invention and therefore also the scope of protection of the patent to be granted o

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Claims (1)

PATENT CLAIMS 1. Procedure for pneumatic braking with trailer leading vehicles in general, with a reaction cylinder-piston unit responds to the air pressure of an air pressure source of the trailer and its movable equipment locking devices of the Air for the trailer brakes builds up for the purpose of changing and switching the action and / or that given to the trailer Braking force, characterized in that a correspondingly adjusted Brake pressure on one end face of the piston (16) of the reaction cylinder piston unit (10-16) is issued while the other end face of this piston is acted upon by the pressure of the compressed air source of the trailer in order to activate the brakes of the trailer to operate in a certain order with respect to the brakes of the tractor, Method according to claim 1, characterized in that one of the end faces of the reaction piston (16) is acted upon by the pressure in the air tank of the trailer and the other Front side by the air pressure controlled by means of throttling devices or limiting devices (4-8.50) Device for carrying out the method according to claim 1, wherein the movable equipment of a reaction cylinder-piston unit responds to the air pressure of the braking system of the trailer and reacts operatively both with the movable equipment of a second reaction-cylinder-piston unit and with a switchable locking member , which brings the actuating means of the trailer brakes either with the trailer air tank or with the outlet in connection, characterized in that pneumatic throttle elements (4-8,50,5 ² O for temporarily changing the air pressure of the trailer air tank and means for acting on this temporarily changed pressure 9098-18 / 100.1 against the face plate of the reaction piston (16) which of those opposite, to which the air pressure of the trailer air tank is applied, in such a way that against the face plates of this reaction piston Differential pressures are issued, which thus cause the tractor's overrun braking. 4) Device according to claim 1, characterized by a pressure reducer (50,5 ^) »whose air chambers (F and G-) are connected to the chambers (B ₁ G) of the reaction cylinder piston unit (10-16) and these chambers are pneumatically connected to one another by means of the throttle body (48, 50) of this pressure reducer, the movable equipment (54) of which is acted upon on one side by the pneumatic pressure which supplies the braking elements of the trailer _{or the like} 5) device according to Ansρ mcη 4, characterized in that the Pressure reducers regulatable organs (60-62) for changing its effect on the pressure controlled by it. 6) Relay valve or trailer brake valve for pneumatic braking systems of trailer vehicles, the resilient piston of which responds to the pressure of the brake system and with a hollow tappet is connected, which combined with switchable shut-off devices which switch the connection of the trailer's braking elements to the trailer's compressed air source or to the outlet, as well as also with a cylinder-reaction piston assembly, its piston is coupled to the first piston in question, characterized in that the chambers (B and G), which from the piston (16) of the Cylinder / reaction piston unit (10-16) are limited, are connected to one another by means of throttling devices (48-50) of a pressure reducer (50-5 ^ 58), the chambers (F and G) of which before and after the throttle element in question with the lower chamber (3) and the upper chamber (G) of the cylinder-reaction piston unit in question are connected to thus changeable in these chambers - 10 - 90581 8/10 0 temporary differential pressures to control the braking of the To build up a trailer 7) Relay valve or trailer valve according to claim. 1, characterized in that the hollow plunger (34) coupled to the piston (18) of the cylinder-reaction piston unit (1CW18) represents a guide element for the piston (16) of the cylinder-reaction piston unit and a shoulder (30 ** 34 ) has as a stop for the reaction piston in question for the purpose of changing and switching the resilient means (28), which are assigned to the first piston (18), whose plunger (34) actuates the switchable shut-off elements (36-38), which supply the braking elements of the Trailer _{cause o} 8. Relay valve or trailer brake valve according to the claims 6 and 7 »marked by the form according to the attached drawing and how relevant for the stated purposes described. §09810 / 1001